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Full text of "The Morphology And Evolution Of The Apes And Man"

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THE  EVOLUTION   OF THE  PEIMATES       329
than those of Propliopithecus; and the canine teeth are larger. The canines are smaller than those in the Gibbons, and the premolars are shorter antero-posteriorly. The mandible itself differs from that in the Gibbons in its longer and narrower symphysis, and in its stronger and relatively deeper body. The angle between the
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mandibular rami is wider than in Parapithecus. The gradual transformation in the characters of the jaw and teeth can be traced in succession through Parapithecus, Propliopithecus and Pliopithecus to Hylobates. Thus we have here one line of ascent from the Eocene Tarsioids to the modern Gibbons ; and it is quite separate from that which leads from Propliopithecus to the Orang, Chimpanzee, Gorilla and Man.
Of the fossil Anthropoids Dryopithecus had the widest distribution, for its remains have been found in many parts of Europe, in Northern Africa and in Northern India. And these have been arranged in several species —D. fontanit D. darwini, D. chinjiensis, D. puiijabicus, D. giganteus, D. rhenanus and D. mogharensis—which are distinguished by differences in the cusps and crena-tion of the enamel of the teeth. The genus also includes fossils which were formerly known as Pliohylobates eppelsheimensis Dubois, and Paidopitliex rhenanus Pohlig. The fossils have received considerable attention from Lartet. Gaudry, Abel, Schlosser, Smith Woodward (514) and others.
The mandible of D. fontani is very heavy. Anteriorly it is deep, and the symphysis descends steeply downwards and backwards. The posterior surface of the symphysis has the usual pit for the genio-hyoid muscles. The pit is bisected by a vertical ridge, which ^ins into